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1.
J Biol Chem ; 300(2): 105654, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38237680

RESUMEN

The mammalian SID-1 transmembrane family members, SIDT1 and SIDT2, are multipass transmembrane proteins that mediate the cellular uptake and intracellular trafficking of nucleic acids, playing important roles in the immune response and tumorigenesis. Previous work has suggested that human SIDT1 and SIDT2 are N-glycosylated, but the precise site-specific N-glycosylation information and its functional contribution remain unclear. In this study, we use high-resolution liquid chromatography tandem mass spectrometry to comprehensively map the N-glycosites and quantify the N-glycosylation profiles of SIDT1 and SIDT2. Further molecular mechanistic probing elucidates the essential role of N-linked glycans in regulating cell surface expression, RNA binding, protein stability, and RNA uptake of SIDT1. Our results provide crucial information about the potential functional impact of N-glycosylation in the regulation of SIDT1-mediated RNA uptake and provide insights into the molecular mechanisms of this promising nucleic acid delivery system with potential implications for therapeutic applications.


Asunto(s)
Proteínas de Transporte de Nucleótidos , ARN , Humanos , Transporte Biológico , Glicosilación , Mamíferos/metabolismo , Proteínas de la Membrana/metabolismo , Proteínas de Transporte de Nucleótidos/metabolismo , ARN/metabolismo
2.
Nano Lett ; 24(5): 1594-1601, 2024 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-38134416

RESUMEN

Blue quantum dot (QD) light-emitting diodes (QLEDs) exhibit unsatisfactory operational stability and electroluminescence (EL) properties due to severe nonradiative recombination induced by large numbers of dangling bond defects and charge imbalance in QD. Herein, dipolar aromatic amine-functionalized molecules with different molecular polarities are employed to regulate charge transport and passivate interfacial defects between QD and the electron transfer layer (ETL). The results show that the stronger the molecular polarity, especially with the -CF3 groups possessing a strong electron-withdrawing capacity, the more effective the defect passivation of S and Zn dangling bonds at the QD surface. Moreover, the dipole interlayer can effectively reduce electron injection into QD at high current density, enhancing charge balance and mitigating Joule heat. Finally, blue QLEDs exhibit a peak external quantum efficiency (EQE) of 21.02% with an operational lifetime (T50 at 100 cd m-2) exceeding 4000 h.

3.
Nano Lett ; 24(19): 5729-5736, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38708832

RESUMEN

Quantum-dot light-emitting diodes (QLEDs), a kind of promising optoelectronic device, demonstrate potential superiority in next-generation display technology. Thermal cross-linked hole transport materials (HTMs) have been employed in solution-processed QLEDs due to their excellent thermal stability and solvent resistance, whereas the unbalanced charge injection and high cross-linking temperature of cross-linked HTMs can inhibit the efficiency of QLEDs and limit their application. Herein, a low-temperature cross-linked HTM of 4,4'-bis(3-(((4-vinylbenzyl)oxy)methyl)-9H-carbazol-9-yl)-1,1'-biphenyl (DV-CBP) with a flexible styrene side chain is introduced, which reduces the cross-linking temperature to 150 °C and enhances the hole mobility up to 1.01 × 10-3 cm2 V-1 s-1. More importantly, the maximum external quantum efficiency of 21.35% is successfully obtained on the basis of the DV-CBP as a cross-linked hole transport layer (HTL) for blue QLEDs. The low-temperature cross-linked high-mobility HTL using flexible side chains could be an excellent alternative for future HTL development.

4.
Environ Sci Technol ; 2024 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-38917348

RESUMEN

The increasing prevalence and persistence of nanoplastics (NPs) have become critical environmental concerns. These particles have the potential to enter the food chain and accumulate in living organisms, which exerts their adverse effects on human health. The release of nanoparticles from feeding bottles raises concerns about potential health issues, especially for newborns exposed to NPs at the neonatal stage. In this study, we examined the impacts of neonatal exposure to polystyrene nanoplastics (PS-NPs) on neurodevelopment. Our study demonstrates that exposure to PS-NPs in newborn mice impairs microglial autophagic function and energy metabolism, leading to the disruption of microglia-mediated synaptic pruning during early neurodevelopment. These mice subsequently develop social behavioral defects in adulthood, suggesting the long-lasting effects of neonatal PS-NP exposure on brain development and behavior. Together, these data provide insights into the mechanism by which PS-NPs affect early neurodevelopment, thus emphasizing the crucial need to address plastic pollution globally.

5.
J Nanobiotechnology ; 22(1): 87, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38429776

RESUMEN

Bone defects remain a significant challenge in clinical orthopedics, but no targeted medication can solve these problems. Inspired by inflammatory targeting properties of macrophages, inflammatory microenvironment of bone defects was exploited to develop a multifunctional nanocarrier capable of targeting bone defects and promoting bone regeneration. The avidin-modified black phosphorus nanosheets (BP-Avidin, BPAvi) were combined with biotin-modified Icaritin (ICT-Biotin, ICTBio) to synthesize Icaritin (ICT)-loaded black phosphorus nanosheets (BPICT). BPICT was then coated with macrophage membranes (MMs) to obtain MMs-camouflaged BPICT (M@BPICT). Herein, MMs allowed BPICT to target bone defects area, and BPICT accelerated the release of phosphate ions (PO43-) and ICT when exposed to NIR irradiation. PO43- recruited calcium ions (Ca2+) from the microenvironment to produce Ca3(PO4)2, and ICT increased the expression of osteogenesis-related proteins. Additionally, M@BPICT can decrease M1 polarization of macrophage and expression of pro-inflammatory factors to promote osteogenesis. According to the results, M@BPICT provided bone growth factor and bone repair material, modulated inflammatory microenvironment, and activated osteogenesis-related signaling pathways to promote bone regeneration. PTT could significantly enhance these effects. This strategy not only offers a solution to the challenging problem of drug-targeted delivery in bone defects but also expands the biomedical applications of MMs-camouflaged nanocarriers.


Asunto(s)
Avidina , Osteogénesis , Avidina/metabolismo , Avidina/farmacología , Biotina , Fototerapia , Macrófagos/metabolismo , Regeneración Ósea , Fósforo/farmacología , Fosfatos
6.
Mol Cancer ; 22(1): 113, 2023 07 17.
Artículo en Inglés | MEDLINE | ID: mdl-37461104

RESUMEN

BACKGROUND: Osteosarcoma (OS) is the most prevalent orthopedic malignancy with a dismal prognosis. The high iron absorption rate in OS cells of patients suggests that ferroptosis may be related to the progression of OS, but its potential molecular regulatory role is still unclear. Based on the ability to couple with exosomes for targeted delivery of signals, exosome-derived micro ribonucleic acids (miRNAs) can potentially serve as diagnostic biomarkers for OS. METHODS: We identified ferroptosis-related miRNAs and messenger ribonucleic acids(mRNAs) in OS using bioinformatics analysis and performed survival analysis. Then we measured miRNA expression levels through exosome microarray sequencing, and used RT-qPCR and IHC to verify the expression level of miR-144-3p and ZEB1. Stable gene expression cell lines were fabricated for in vitro experiments. Cell viability, migration and invasion were determined by CCK-8 and transwell experiment. Use the corresponding reagent kit to detect GSH/GSSG ratio, Fe2+ level, MDA level and ROS level, and measure the expression levels of GPX4, ACSL4 and xCT through RT-qPCR and WB. We also constructed nude mice model for in vivo experiments. Finally, the stability of the miRNA/mRNA axis was verified through functional rescue experiments. RESULTS: Low expression of miR-144-3p and high expression of ZEB1 in OS cell lines and tissues was observed. Overexpression of miR-144-3p can promote ferroptosis, reduce the survival ability of OS cells, and prevent the progression of OS. In addition, overexpression of miR-144-3p can downregulate the expression of ZEB1 in cell lines and nude mice. Knockdown of miR-144-3p has the opposite effect. The functional rescue experiment validated that miR-144-3p can regulate downstream ZEB1, and participates in the occurrence and development of OS by interfering with redox homeostasis and iron metabolism. CONCLUSIONS: MiR-144-3p can induce the occurrence of ferroptosis by negatively regulating the expression of ZEB1, thereby inhibiting the proliferation, migration, and invasion of OS cells.


Asunto(s)
Neoplasias Óseas , Exosomas , Ferroptosis , MicroARNs , Osteosarcoma , Animales , Ratones , Neoplasias Óseas/patología , Línea Celular Tumoral , Proliferación Celular/genética , Exosomas/metabolismo , Ferroptosis/genética , Hierro , Ratones Desnudos , MicroARNs/genética , MicroARNs/metabolismo , Osteosarcoma/patología , Humanos
7.
J Transl Med ; 21(1): 216, 2023 03 23.
Artículo en Inglés | MEDLINE | ID: mdl-36959674

RESUMEN

BACKGROUND: The impact of metabolically healthy obesity (MHO) on kidney dysfunction remains debatable. Moreover, few studies have focused on the early stages of kidney dysfunction indicated by hyperfiltration and mildly reduced eGFR. Thus, we aimed to investigate the association between the MHO and early kidney dysfunction, which is represented by hyperfiltration and mildly reduced estimated glomerular filtration rate (eGFR), and to further explore whether serum uric acid affects this association. METHODS: This cross-sectional study enrolled 1188 residents aged ≥ 40 years old from Yonghong Communities. Metabolically healthy phenotypes were categorized based on Adult Treatment Panel III criteria. Obesity was defined as body mass index (BMI) ≥ 25 kg/m2. Mildly reduced eGFR was defined as being in the range 60 < eGFR ≤ 90 ml/min/1.73m2. Hyperfiltration was defined as eGFR > 95th percentile after adjusting for sex, age, weight, and height. RESULTS: Overall, MHO accounted for 12.8% of total participants and 24.6% of obese participants. Compared to metabolically healthy non-obesity (MHNO), MHO was significantly associated with an increased risk of mildly reduced eGFR (odds ratio [OR] = 1.85, 95% confidence interval [CI] 1.13-3.01) and hyperfiltration (OR = 2.28, 95% CI 1.03-5.09). However, upon further adjusting for uric acid, the association between the MHO phenotype and mildly reduced eGFR was reduced to null. Compared with MHNO/non-hyperuricemia, MHO/non-hyperuricemia was associated with an increased risk of mildly reduced eGFR (OR = 2.04, 95% CI 1.17-3.58), whereas MHO/hyperuricemia was associated with an observably increased risk (OR = 3.07, 95% CI 1.34-7.01). CONCLUSIONS: MHO was associated with an increased risk of early kidney dysfunction, and the serum uric acid partially mediated this association. Further prospective studies are warranted to clarify the causality.


Asunto(s)
Obesidad Metabólica Benigna , Insuficiencia Renal , Humanos , Obesidad Metabólica Benigna/complicaciones , Ácido Úrico , Tasa de Filtración Glomerular , Factores de Riesgo , Estudios Transversales , Obesidad/complicaciones , Obesidad/genética , Índice de Masa Corporal
9.
Cell Biol Int ; 47(8): 1344-1353, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-36987947

RESUMEN

Bufalin, a major cardiotonic compound of the traditional Chinese medicine Chanshu has been used for cancer treatment for several years. However, the molecular mechanisms of Bufalin-induced autophagy in osteosarcoma (OS) is not fully understood. In the present study, it was shown that Bufalin induced crosstalk between apoptosis and autophagy, which resulted in OS cell death. Mechanistically, Bufalin induced autophagy by increased the ratio of microtubule-associated protein 1A/1B-light chain 3 (LC3)-II/LC3-I, and inducing apoptosis via the caspase-dependent pathway. Inhibition of autophagy promoted Bufalin-induced cell death. In contrast, suppression of apoptosis enhanced Bufalin-induced autophagy. In addition, it was found that Bufalin activated the Ca2+ /calmodulin-dependent protein kinase ß/AMPK/Beclin1 pathway, which resulted in induction of autophagy. These findings provide a mechanistic understanding of the means by which Bufalin mediates autophagy and apoptosis in OS cells.


Asunto(s)
Quinasa de la Proteína Quinasa Dependiente de Calcio-Calmodulina , Osteosarcoma , Humanos , Beclina-1 , Quinasa de la Proteína Quinasa Dependiente de Calcio-Calmodulina/metabolismo , Proteínas Quinasas Activadas por AMP/metabolismo , Calcio/metabolismo , Línea Celular Tumoral , Transducción de Señal , Apoptosis , Autofagia , Osteosarcoma/tratamiento farmacológico , Osteosarcoma/metabolismo
10.
Circ J ; 87(7): 964-972, 2023 06 23.
Artículo en Inglés | MEDLINE | ID: mdl-37225477

RESUMEN

BACKGROUND: Previous studies revealed a relationship between 8-hydroxy-2'-deoxyguanosine (8-OHdG) and the occurrence/recurrence of atrial fibrillation (AF). This 2-part study aimed to validate whether DNA damage related to 8-OHdG is associated with left atrial (LA) fibrosis in AF patients quantified by voltage mapping (Part I), and to identify the underlying genetic components regulating the 8-OHdG level (Part II).Methods and Results: Plasma 8-OHdG determination, DNA extraction, and genotyping were conducted before catheter ablation. LA voltage mapping was performed under sinus rhythm. According to the percentage of low voltage area (LVA), patients were categorized as stage I (<5%), stage II (5-10%), stage III (10-20%), and stage IV (>20%). Part I included 209 AF patients. The 8-OHdG level showed an upward trend together with advanced LVA stage (stage I 8.1 [6.1, 10.5] ng/mL, stage II 8.5 [5.7, 14.1] ng/mL, stage III 14.3 [12.1, 16.5] ng/mL, stage IV 13.9 [10.5, 16.0] ng/mL, P<0.000). Part II included 175 of the 209 patients from Part I. Gene-set analysis based on genome-wide association study summary data identified that the gene set named 'DNA methylation on cytosine' was the only genetic component significantly associated with 8-OHdG concentration. CONCLUSIONS: Higher 8-OHdG levels may predict more advanced LVA of the LA in AF patients. DNA methylation is the putative genetic component underlying oxidative DNA damage in AF patients.


Asunto(s)
Fibrilación Atrial , Ablación por Catéter , Humanos , 8-Hidroxi-2'-Desoxicoguanosina , Metilación de ADN , Estudio de Asociación del Genoma Completo , Atrios Cardíacos , Biomarcadores , Fibrosis , Ablación por Catéter/métodos , Recurrencia , Resultado del Tratamiento
11.
Eur J Nutr ; 62(1): 199-211, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-35933635

RESUMEN

AIMS: Overconsumption of sugar-sweetened beverages (SSBs) is associated with an increased risk of metabolic disorders, including obesity and diabetes. However, accumulating evidence also suggests the potential negative impact of consuming nonnutritive sweeteners (NNSs) on weight and glycaemic control. The metabolic effects of sucralose, the most widely used NNS, remain controversial. This study aimed to compare the impact of intake of dietary sucralose (acceptable daily intake dose, ADI dose) and sucrose-sweetened water (at the same sweetness level) on lipid and glucose metabolism in male mice. MATERIALS AND METHODS: Sucralose (0.1 mg/mL) or sucrose (60 mg/mL) was added to the drinking water of 8-week-old male C57BL/6 mice for 16 weeks, followed by oral glucose and intraperitoneal insulin tolerance tests, and measurements of bone mineral density, plasma lipids, and hormones. After the mice were sacrificed, the duodenum and ileum were used for examination of sweet taste receptors (STRs) and glucose transporters. RESULTS: A significant increase in fat mass was observed in the sucrose group of mice after 16 weeks of sweetened water drinking. Sucrose consumption also led to increased levels of plasma LDL, insulin, lipid deposition in the liver, and increased glucose intolerance in mice. Compared with the sucrose group, mice consuming sucralose showed much lower fat accumulation, hyperlipidaemia, liver steatosis, and glucose intolerance. In addition, the daily dose of sucralose only had a moderate effect on T1R2/3 in the intestine, without affecting glucose transporters and plasma insulin levels. CONCLUSION: Compared with mice consuming sucrose-sweetened water, daily drinking of sucralose within the ADI dose had a much lower impact on glucose and lipid homeostasis.


Asunto(s)
Ingestión de Líquidos , Intolerancia a la Glucosa , Masculino , Animales , Ratones , Agua , Ratones Endogámicos C57BL , Sacarosa/efectos adversos , Glucosa/metabolismo , Insulina , Lípidos
12.
Pacing Clin Electrophysiol ; 46(11): 1379-1386, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37943014

RESUMEN

BACKGROUND: Persistent left superior vena cava (PLSVC) is the most prevalent form of thoracic venous abnormality and can serve as a significant arrhythmogenic source in atrial fibrillation (AF). METHODS AND RESULTS: Among the 3950 patients who underwent radiofrequency ablation for AF between September 2014 to April 2020, 17 patients (mean age 59.4 ± 8.0 years, 64.7% male) with PLSVC were identified. Among them, nine patients (52.9%) had a prior history of pulmonary vein isolation (PVI) alone. Eight out of nine patients who experienced AF recurrence underwent PLSVC isolation with or without pulmonary vein (PV) reconnection. For the remaining eight patients (47.1%), PVI plus PLSVC isolation were performed during the index procedure. Ectopy originating from PLSVC was documented in 11 patients (64.7%) and successful PLSVC isolation was achieved in 16 patients (94.1%). After a median follow-up of 28.3 months, freedom from AF/ atrial tachycardia (AT) was observed in 13 patients (76.5%). CONCLUSION: Empirical PLSVC isolation beyond PVI appears to be a feasible and safe strategy to prevent AF recurrence in patients with concomitant PLSVC.


Asunto(s)
Fibrilación Atrial , Ablación por Catéter , Vena Cava Superior Izquierda Persistente , Venas Pulmonares , Taquicardia Supraventricular , Humanos , Masculino , Persona de Mediana Edad , Anciano , Femenino , Vena Cava Superior Izquierda Persistente/complicaciones , Vena Cava Superior , Ablación por Catéter/métodos , Venas Pulmonares/cirugía , Recurrencia , Resultado del Tratamiento
13.
Pacing Clin Electrophysiol ; 46(7): 752-760, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37221974

RESUMEN

BACKGROUND: It is inevitable for patients to have a temporary or permanent pacemaker implanted during or after radiofrequency catheter ablation (RFCA) for treatment of atrial fibrillation (AF) in some cases. The aim of our study was to evaluate the incidence of pacemaker implantation (PMI) during or within 3 months of RFCA for AF and to identify the risk factors that were associated with PMI. METHODS: We performed a retrospective analysis of consecutive AF patients who underwent RFCA between August 2018 and October 2020 at our center. The incidence of PMI within 3 months during or after RFCA were assessed. A multivariate logistic regression model was performed to identify predictors of PMI. RESULTS: One thousand and five patients (mean age, 60.2 ± 10.3 years; 37.6% women) were included in this analysis. PVI was performed in all patients. A total of 23 (2.3%) patients had a pacemaker implanted within 3 months during or after ablation. Multivariable logistic regression analysis revealed that older age (OR: 1.08 [95% CI 1.03-1.13], p = .003), female sex (OR: 3.08 [95% CI 1.28-7.45], p = .012), paroxysmal AF (OR: 4.71 [95% CI 1.09-20.45], p = .038) and repeated ablation (OR: 2.78 [95% CI 1.04-7.40], p = .041) were the independent predictors for PMI. CONCLUSIONS: Older age, female sex, paroxysmal AF and repeated ablation were identified as predictive risk factors for PMI after RFCA in patients with AF. A "watch and wait" strategy could be taken for patients with temporary PMI after ablation, especially for those with prolonged sinus pause after AF termination.


Asunto(s)
Fibrilación Atrial , Ablación por Catéter , Marcapaso Artificial , Humanos , Femenino , Persona de Mediana Edad , Anciano , Masculino , Estudios Retrospectivos , Resultado del Tratamiento , Ablación por Catéter/efectos adversos , Recurrencia
14.
BMC Nephrol ; 24(1): 364, 2023 12 08.
Artículo en Inglés | MEDLINE | ID: mdl-38066475

RESUMEN

Lipoprotein(a) [Lp(a)] is a risk factor for cardiovascular disease (CVD) and aortic stenosis. However, the data on the relationship between Lp(a) and mildly reduced estimated glomerular filtration rate (eGFR) has been disputed. This study was conducted to assess the relationship between Lp(a) concentrations and mildly reduced eGFR in healthy subjects.This community-based, cross-sectional study enrolled 1,064 volunteers aged ≥ 40 years who lived in Yonghong Community, Zhonglou District, Changzhou, China, between December 2016 and December 2017. A mildly reduced eGFR was defined as eGFR between 60 and 90 mL/min/1.73m2. A standardized questionnaire and biochemical measurements were used to gather information about participants. The serum concentration of Lp(a) was determined using the latex-enhanced immunoturbidimetric test. Of the total study population, 34.8% (n = 370) were men, and the mean age was 66.8 ± 8.5 years. A significant association existed between Lp(a) levels and the risk of mildly reduced eGFR. Individuals with the highest tertile of Lp(a) had higher odds of mildly reduced eGFR after adjusting for various confounders (adjusted odds ratio [OR]: 1.80, 95% confidence interval [CI]: 1.24-2.60, P = 0.0025) compared to those with the lowest tertile of Lp(a). Multivariable logistic regression of studies in which Lp(a) was presented as continuous variables showed consistent results (adjusted OR: 1.23 for 1-SD increment of Ln-Lp(a), 95% CI: 1.05-1.43). Subgroup analyses showed that study characteristics such as age, sex, obesity, diabetes, and hypertension status did not significantly affect the association (P for all interactions > 0.05). These results suggest that higher serum Lp(a) level was an independent risk factor for mildly reduced eGFR.


Asunto(s)
Tasa de Filtración Glomerular , Lipoproteína(a) , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Transversales , Lipoproteína(a)/sangre , Obesidad , Factores de Riesgo
15.
BMC Public Health ; 23(1): 849, 2023 05 10.
Artículo en Inglés | MEDLINE | ID: mdl-37165358

RESUMEN

BACKGROUND: Hand, foot and mouth disease (HFMD) caused by a variety of enteroviruses remains a major public health problem in China. Previous studies have found that social factors may contribute to the inconsistency of the relationship patterns between meteorological factors and HFMD, but the conclusions are inconsistent. The influence of social factors on the association between meteorology and HFMD is still less well understood. We aimed to analyze whether social factors affected the effect of meteorological factors on HFMD in Sichuan Province. METHOD: We collected daily data on HFMD, meteorological factors and social factors in Sichuan Province from 2011 to 2017. First, we used a Bayesian spatiotemporal model combined with a distributed lag nonlinear model to evaluate the exposure-lag-response association between meteorological factors and HFMD. Second, by constructing the interaction of meteorological factors and social factors in the above model, the changes in the relative risk (RR) under different levels of social factors were evaluated. RESULTS: The cumulative exposure curves for average temperature, relative humidity, and HFMD were shaped like an inverted "V" and a "U" shape. As the average temperature increased, the RR increased and peaked at 19 °C (RR 1.020 [95% confidence interval CI 1.004-1.050]). The urbanization rate, per capita gross domestic product (GDP), population density, birth rate, number of beds in health care centers and number of kindergartens interacted with relative humidity. With the increase in social factors, the correlation curve between relative humidity and HFMD changed from an "S" shape to a "U" shape. CONCLUSIONS: Relative humidity and average temperature increased the risk of HFMD within a certain range, and social factors enhanced the impact of high relative humidity. These results could provide insights into the combined role of environmental factors in HFMD and useful information for regional interventions.


Asunto(s)
Enfermedad de Boca, Mano y Pie , Humanos , Enfermedad de Boca, Mano y Pie/epidemiología , Incidencia , Teorema de Bayes , Temperatura , Conceptos Meteorológicos , China/epidemiología
16.
Small ; 18(48): e2205227, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36285770

RESUMEN

Ultrathin hybrid perovskites, with exotic properties and two-dimensional geometry, exhibit great potential in nanoscale optical and optoelectronic devices. However, it is still challenging for them to be compatible with high-resolution patterning technology toward miniaturization and integration applications, as they can be readily damaged by the organic solvents used in standard lithography processes. Here, a flexible three-step method is developed to make high-resolution multicolor patterning on hybrid perovskite, particularly achieved on a single nanosheet. The process includes first synthesis of precursor PbI2 , then e-beam lithography and final conversion to target perovskite. The patterns with linewidth around 150 nm can be achieved, which can be applied in miniature optoelectronic devices and high-resolution displays. As an example, the channel length of perovskite photodetectors can be down to 126 nm. Through deterministic vapor-phase anion exchange, a perovskite nanosheet can not only gradually alter the color of the same pattern in a wide wavelength range, but also display different colors simultaneously. The authors are optimistic that the method can be applied for unlimited perovskite types and device configurations for their high-integrated miniature applications.

17.
Horm Metab Res ; 54(10): 677-685, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36206761

RESUMEN

Lipocalin-2 (LCN2) is becoming recognized as a pleiotropic mediator of metabolic disorders. However, the relationship between LCN2 and gestational diabetes mellitus (GDM) is not well understood. We performed a systematic review and meta-analysis to explore it. A systematic search of Cochrane Library, PubMed, Embase, Scopus, Web of Science, Chinese National Knowledge Infrastructure, and Wan-fang Database was done for relevant articles published up to September 29, 2021. Standardized mean difference (SMD) with 95% confidence intervals (CI) was calculated to explore the association of LCN2 levels with GDM using Revman 5.3 and Stata 15.1. Fifteen case-control studies were included in this meta-analysis. The patients with GDM had significantly higher levels of blood LCN2 than parturients with normal glucose tolerance (SMD=3.41, 95% CI=2.24 to 4.58). Meta-regression and subgroup analysis were conducted to investigate the source of heterogeneity. Likely sources of heterogeneity were age and testing methods. This study found that GDM showed higher blood LCN2 levels than controls. However, caution is warranted on the interpretation of these findings. Standardized LCN2 measurement methods and longitudinal studies are required to disentangle and better understand the relationships observed.


Asunto(s)
Diabetes Gestacional , Lipocalina 2/sangre , Estudios de Casos y Controles , Femenino , Glucosa , Humanos , Embarazo
18.
Nano Lett ; 21(24): 10292-10300, 2021 12 22.
Artículo en Inglés | MEDLINE | ID: mdl-34846904

RESUMEN

Biomineralization generates hierarchically structured minerals with vital biological functions in organisms. This strategy has been adopted to construct complex architectures to achieve similar functionalities, mostly under chemical environments mimicking biological components. The molecular origin of the biofacilitated mineralization process is elusive. Herein, we describe the mineralization of hydroxyapatite (HAp) accompanying the biological secretion of nanocellulose by Acetobacter xylinum. In comparison with mature cellulose, the newly biosynthesized cellulose molecules greatly accelerate the nucleation rate and facilitate the uniform distribution of HAp crystals, thereby generating composites with a higher Young modulus. Both simulations and experiments indicate that the biological metabolism condition allows the easier capture of calcium ions by the more abundant hydroxyl groups on the glucan chain before the formation of hydrogen bonding, for the subsequent growth of HAp crystals. Our work provides more insights into the biologically accelerated mineralization process and presents a different methodology for the generation of biomimetic nanocomposites.


Asunto(s)
Durapatita , Nanocompuestos , Biomimética/métodos , Biomineralización , Celulosa/química , Durapatita/química , Nanocompuestos/química
19.
AAPS PharmSciTech ; 23(3): 76, 2022 Feb 17.
Artículo en Inglés | MEDLINE | ID: mdl-35178657

RESUMEN

The preparation of drugs into nanocrystals represents a practical pharmaceutical technology to solubilize poorly water-soluble drugs and enhance bioavailability. However, commonly used stabilizers in nanocrystals like polymers and surfactants are frequently inefficient and cannot stabilize nanocrystals for an expected time. This study reports an exquisite platform for nanocrystal production based on a metal-phenolic network (MPN). MPN-wrapped nanocrystal particles (MPN-NPs) were fabricated through an anti-solvent precipitation method using tannic acid and FeIII or AlIII as coupling agents and characterized by dynamic light scattering, transmission electron microscope, ultraviolet and visible spectrophotometry, fourier-transform infrared spectroscopy, and X-ray powder diffraction. In vitro release, cytotoxicity, and stability were mainly studied with MPN-NPs loading paclitaxel. The suitability of MPN as a nanocrystal stabilizer was also investigated for other classical hydrophobic drugs, including simvastatin, andrographolide, atorvastatin calcium, ferulic acid, and famotidine. The results showed that MPN could effectively wrap and stabilize various drug nanocrystals apart from famotidine. The maximum solubilization of MPN towards atorvastatin calcium was up to 1587 folds, and it also exhibited an excellent solubilizing effect on other hydrophobic drugs. We disclosed that the drug was entrapped in MPN in the nanocrystal form, and there were distinct physiochemical interactions between MPN and the payload. Our findings suggested that MPN may be a promising platform for nanocrystal production to address the challenge of low solubility associated with hydrophobic drugs. Graphical abstract.


Asunto(s)
Compuestos Férricos , Nanopartículas , Excipientes , Nanopartículas/química , Tamaño de la Partícula , Solubilidad
20.
Entropy (Basel) ; 24(5)2022 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-35626523

RESUMEN

Mobile crowdsensing (MCS) is attracting considerable attention in the past few years as a new paradigm for large-scale information sensing. Unmanned aerial vehicles (UAVs) have played a significant role in MCS tasks and served as crucial nodes in the newly-proposed space-air-ground integrated network (SAGIN). In this paper, we incorporate SAGIN into MCS task and present a Space-Air-Ground integrated Mobile CrowdSensing (SAG-MCS) problem. Based on multi-source observations from embedded sensors and satellites, an aerial UAV swarm is required to carry out energy-efficient data collection and recharging tasks. Up to date, few studies have explored such multi-task MCS problem with the cooperation of UAV swarm and satellites. To address this multi-agent problem, we propose a novel deep reinforcement learning (DRL) based method called Multi-Scale Soft Deep Recurrent Graph Network (ms-SDRGN). Our ms-SDRGN approach incorporates a multi-scale convolutional encoder to process multi-source raw observations for better feature exploitation. We also use a graph attention mechanism to model inter-UAV communications and aggregate extra neighboring information, and utilize a gated recurrent unit for long-term performance. In addition, a stochastic policy can be learned through a maximum-entropy method with an adjustable temperature parameter. Specifically, we design a heuristic reward function to encourage the agents to achieve global cooperation under partial observability. We train the model to convergence and conduct a series of case studies. Evaluation results show statistical significance and that ms-SDRGN outperforms three state-of-the-art DRL baselines in SAG-MCS. Compared with the best-performing baseline, ms-SDRGN improves 29.0% reward and 3.8% CFE score. We also investigate the scalability and robustness of ms-SDRGN towards DRL environments with diverse observation scales or demanding communication conditions.

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